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%I #4 Apr 28 2014 09:46:54
%S 1,1,2,3,15,16,29,41,65,144,179,269,382,549,739,1286,1564,2254,2978,
%T 4124,5304,7264,10157,12941,17027,22194,28663,36884,47306,59837,79467,
%U 98114,125117,156392,198113,244710,307908,378429,471337,588642,721300,884498
%N Number of compositions of n into distinct parts with exactly two descents.
%H Alois P. Heinz, <a href="/A241721/b241721.txt">Table of n, a(n) for n = 6..1000</a>
%e a(9) = 3: [6,2,1], [5,3,1], [4,3,2].
%e a(10) = 15: [5,4,1], [7,2,1], [6,3,1], [5,3,2], [4,1,3,2], [2,1,4,3], [4,3,1,2], [4,2,3,1], [2,4,3,1], [1,4,3,2], [3,1,4,2], [3,2,4,1], [3,4,2,1], [4,2,1,3], [3,2,1,4].
%Y Column k=2 of A241719.
%K nonn
%O 6,3
%A _Alois P. Heinz_, Apr 27 2014